Self-trailing boats



Jan. 4, 1966 F. K. FOX

SELF-TRAILING BOATS 5 Sheets-Sheet 1 Filed Nov. 25, 1964 Fred Fox INVENTOR.

Jan. 4, 1966 F. K. FOX 3,226,738

SELF-TRAILING BOATS Filed Nov. 25, 1964 5 Sheets-Sheet 2 Fred ffl Fox INVENTOR.

ATTO/M/fVJ Jan. 4, 1966 F. K. FOX 3,226,738

SELF-TRAILING BOATS Filed Nov. 25, 1964 5 Sheets-Sheet 5 Fr e 0 A. F 0 x INVENTOR.

ATTO/PNE VJ Jan. 4, 1966 F. K. FOX 3,226,738

SELF-TRAILING BOATS Filed Nov. 25, 1964 5 Sheets-Sheet 4 Fred K. Fox

INVENTOR.

BY 1 M I ,i/ r i 21 Jan. 4, 1966 F. K. FOX 3,226,738

SELF-TRAILING BOATS Filed No v. 25, 1964 s Sheets-Sheet 5 Free K Fox INVENTOR.

ATTO/F/VEVJ United States Patent ,7 8 SELF-TRAILING BOATS Fred K. Fox, 242 Stoney Creek Drive, Houston, Tex.

Filed Nov. 25, 1964, Ser. No. 416,168

20 Claims. Cl. 9-1) This application is a continuation-impart of my copending application, Serial No. 268,021, filed March 26, 1963, now abandoned, and entitled Self-Trailing Boat.

This invention relates to improvements in boats which are self trailing in the sense that they have wheels for movement over the land and therefore do not have to be loaded onto or from a separatetrailer as they are taken from or placed in the water. In one of its aspects, this invent-ion relates to improvements in self-trailing boats of the Catamaran or Hydrofoil type wherein elements,

such as sideboards .and foils, depend from the hull inithe normal operation of the boat in the water.

In prior self-trailing boats, it has been proposed to permanently mount wheels having rubber tires in laterally spaced-apart openings or wells on opposite sides of the boat hull. If these wheels are left in a lowered, ground engaging position when the boat is in the water, this will, of course, slow the boat down considerably. Even when provision is made for retracting such wheels into the wells when the boat is in the water, the surface of the hull of many of these prior boats is severely interrupted, which has no doubt made them too impractical for use. Furthermore, whether lowered or retracted, these wheels includ ing the tires add Weight to the boat, and, when left in the water for great lengths of time, will become corroded and deteriorated. Over and above the foregoing, the equipment heretofore provided for mounting such wheels has been of complex and expensive construction. w

As far as I know, "such wheels have not beenemployed in the Catamaran or Hydrofoil type boat, probably because thedepending elements on the hull of this type of boat would interfere with trailing. Also, if located in the manner heretofore proposed, such wheels would interfere with the Sideboards or foils. Apart from this, even if it were practical to mount the wheels in non-interfering positions and the depending elements were, similarly to the wheels, retractably mounted in wells in the boat hull, the resulting hull would be of extremely complicated construction and would severely limit passenger space in theboat.

An object of this invention is to provide a self-trailing boat which may be converted to a normal operating condition in which there is little or no drag or resistance to its movement within the water, and preferably, inwhich the weight of the boat is only slightly greater than an ordinary boat of the same size.

, Another object is to provide such a boat which i so converted by the replacement of the wheelswith a part having a surface which provides at least a substantial continuation of the boat hull, wherein such replacement is accomplished with a minimum of effort, and particularly while the boat is in the water and thus supportedby its buoyant eflfect. I

. Still another object is to provide a self-trailing Catamaran or Hydrofoil type boat having elements normally depending from its hull but which is convertible to a self-. trailing condition by means :of wheels mounted in such a manner as to not interfere with such elements.

Yet another object is to provide a self-trailing boat of the type above described in which the wheels are mounted in openings or wells in the hull thereof in a simple and inexpensive manner.

. A further object is to provide a self-trailing boat having a hitch for attachment to the towing vehicle which is so 70 arranged as to reduce the likelihood of damage to the Patented J an. 4, 1966 ance with the illustrated embodiments of the present invention, by a boat which comprises, as in prior self-trailing boats, a hull having two or more laterally spacedapart openings or wells in its bottom side. As distinguished from prior boats of this type, however, my selftrailing boat. also has means including a wheel and a surface providing at least a substantial continuation of the boat .hull which are interchangeably securable within each saidI-opening to permit the boat to be converted between a self trailing condition and a normal water operat ing condition.

In one embodiment of my invention, the wheel and boat hull continuation surface are connected to one another as a single assembly for end-to-end reversal during such conversion. Although this embodiment has the advantage of simplicity, the presence of the wheels in the nor- Since both the wheels and depending elements are carried by one or more assemblies securable with the same hull opening, the boat has the same capacity which it would have if r it were merely a conventional self-trailing boat of the smooth hull variety. At the same time, the interchange of the boat hull continuation surface with the wheel to convert the boat to self-trailing condition avoids any concern over the possible interference of the depen ing elements with the groundsurf-ace.

The interchange of the wheel and boat hull continuation surface without having to lift the boat from the water is made possible by a well or opening whose upper end extends above the water line of the boat when in a fully loaded condition. Thus, it is' not necessary to seal off the upper end of the opening, and these parts, whether connected end to end in a single assembly or carried by separate assemblies, may be moved through the upper end of such opening during conversion while the weight of the boat is supported by the water. 7

In the preferred embodiment of the invention, there is an upwardly facing shoulder in each opening or well and a downwardly facing shoulder on each assembly for seating upon the shoulder in the opening to locate the wheel or boat hull continuation surface in proper position. In addition, there is a means for holding the as sembly shoulder down upon the shoulder in the hull opening, which preferably includes a removable cover for the top end of the hull opening and suitable means for releasably holding the cover over such opening. A resilient means of some kind, such as an air spring, may be disposed between this hold down means and the top side of the assembly within the hull opening in order to provide a cushion or shock absorber, which is particularly useful when the boat is in 'a self-trailing condition although also useful when there is an element depending from the boat hul l continuation surface which might otherwise be damaged in encountering an obstruction below the water surface. i

Each hull opening is preferably generally rectangular intermediate its upper and lower ends and each assembly includes a frame having a similar shape adapted to fit relatively closely within such opening. More particularly, the frame fits sufiiciently closely to lend stability to the wheel or depending element thereon, but not necessarily in sealtight relation which might complicate installation, because, as noted above, the upper end of the hull opening is above the normal water line of the boat. The front and rear sides of each hull opening preferably slant upwardly and rearwardly with respect to the end of the boat to which the hitch is connected so that the forces on the wheel or depending element will permit the frame to move into the hull opening in the direction of the resultant force vector.

In a further preferred embodiment of the invention, the hitch is connected to the rear end of the boat hull, and particularly to the transom which is the strongest portion of a boat of a size suitable for trailing, and which thereby provides a maximum of resistance to the stresses imposed on the boat by the towing vehicle. Furthermore, this arrangement of the hitch places the weight of the rearmounted motor in such a location as to reduce to a minimum the possibility of sidewise sway of the boat during trailing.

In the drawings, wherein like reference characters are used throughout to designate like parts:

FIG. 1 is a side elevational view of a semi multi-hull type boat in self-trailing condition and having its central portion broken away to illustrate a wheel assembly secured within an opening or Well at one side of the hull in accordance with the present invention;

FIG. 2 is a cross-sectional view of a .part of the boat of FIG. 1, as seen along broken line 2-2 thereof and illustrating the front end of the wheel assembly;

FIG. 3 is a front end view of the boat of FIGS. 1 and 2 in normal operating condition and with a portion thereof broken away to illustrate the front end of another assembly including a surface providing a smooth continuation of the boat hull which is secured within the hull opening to replace the wheel assembly;

FIG. 4 is a'longitudinal sectional view of a portion of the boat of FIGS. 1 to 3, as seen along broken line 4-4 of FIG. 3 and illustrating the outer side of the other assembly shown in FIG. 3;

FIG. 5 is a side elevational view of a Hydrofoil type boat having a central portion thereof broken away in part to illustrate an assembly secured within an opening in the hull of the boat in accordance with the present invention so as to mount a rearwardly disposed foil depending therefrom in a position for gliding through the water;

FIG. 6 is a cross-sectional view of a portion of the boat of FIG. 5, as seen along broken line 6-6 of FIG. 5 and illustrating the front side of a similar assembly mounting one of the forward foils;

FIG. 7 is a side elevational view of relatively fiat-bottomed, self-trailing boat having a hitch connected to the transom thereof in accordance with a preferred embodiment of the invention;

FIG. 8 is an enlarged perspective view of the hitch shown in FIG. 7;

FIG. 9 is a longitudinal sectional view of a portion of a self-trailing boat having assembly secured Within an opening in the boat hull thereof and mounting a wheel in trailing position in accordance with another embodiment of the present invention;

FIG. 10 is a view similar to FIG. 9, but in which the assembly has been reversed end-for-end and secured within the hull opening to dispose a surface thereon as a smooth continuation of the boat hull so as to convert the boat to normal operating condition;

FIG. 11 is a front end view of a Catamaran type boat having a wheel mounted in each separate body of the hull thereof to render it self-trailing in accordance with another embodiment of the present invention;

FIG. 12 is a top plan view of the boat of FIG. 11, illustrating in broken lines the position of the hull openings;

FIG. 13 is a side elevational view of the boat of FIGS.

11 and 12 upon conversion to normal operating condition, wherein the wheel assemblies have been replaced by assemblies carrying sideboards;

FIG. 14 is a longitudinal sectional view of a portion of the boat of FIGS. 11 to 13, and illustrating the outer side of the assembly carrying the sideboard shown in FIG. 13;

FIG. 15 is a longitudinal sectional view of a portion of a modified form of Catamaran type boat in its normal operating condition;

FIG. 16 is a cross sectional view of the boat of FIG. 15, as seen along broken line 1616 thereof; and

FIG. 17 is a view similar to FIG. 15, but with the boat shown therein converted to self-trailing condition.

With reference now to the details of the above-described figures, the hull 10 of the boat shown in FIGS. 1 to 4 comprises three relatively distinct longitudinally extending hull bodies 11. As distinguished from the Catamaran type boat, however, the bodies 11 of the hull are connected by portions 12 which are below the water lever 13 in the fully loaded position of the boat. In any case, however, the boat shown in FIGS. 1 to 4 is one of many types of relatively flat-bottomed boats which are susceptible of conversion to self-trailing condition in accordance with the present invention.

As shown in FIG. 1, this boat is powered by means of an outboard motor 14 carried at the rear end 15 of the hull and swingable, in the trailing position of the boat, to a relatively horizontal position in which the propeller is removed from danger. Obviously, however, other means may be used to propel this boat, such as an air type propeller at the rear end of an air boat or an air cushion. As in conventional boats of this type, there is a relatively large passenger area in the interior of the hull which includes a seat 16 for the driver and a windshield 17 forwardly of the seat and projecting above the top side of the hull. When in self-trailing condition, as shown in FIGS. 1 and 2, the boat is towed over the ground level 22 by a vehicle to which it is connected by means of a hitch 18 connected to the front end of the hull in any suitable manner and including a socket 19 on its front end for connection to a ball-type joint on the rear end of the hitch 20 extending from the rear of the towing vehicle (not shown). conventionally a hitch of this type will also include a small wheel 21 which will hold the boat up off the ground level 22 as the hitch is connected and disconnected.

In accordance with the present invention, the opening or well 23 in the bottom side of each of the outermost hull bodies 11 is preferably disposed with its center just rearwardly of the center of gravity of the boat-i.e., in a direction away from its towing end. As can be seen from FIGS. 1 to 4, the front and rear walls 24 and 25, respectively, as well as the side walls 26 forming the opening 23 extend upwardly above the water level 13, so that it is not essential to sealably close off the upper end of the hull opening since the water will assume a similar level within it.

As shown in FIGS. 1 and 2, in the self-trailing condition of the boat, a wheel 28 carried by the frame 29 of the wheel assembly 27 secured within the hull opening depends from the bottom of the hull a sufiicient distance to raise the bottom side of the hull a safe distance above the ground level. More particularly, the frame 29 is hollow to receive the upper portion of the wheel 28 and, similarly to the opening 23, is generally rectangular in cross section so as to fit rather closely within the opening. There is a shoulder 30 within the opening which faces upwardly to support a corresponding shoulder 31 about the frame 29. When the shoulder 31 is seated upon the hull opening shoulder 30, the assembly may be held down in such position, in a manner to be described, to maintain the wheel 28, which is carried about an axle 32 mounted upon an extension 33 depending from the opposites of the lower end of the frame 29, in engagement with the ground level 22. As shown in FIG. 1, the sides of the frame 'may have openings therein to reduce its weight to a minimum.

The wheel assembly 27 is held down in trailing position by means of a cover 34 releasably connectible over the top end of opening 23 and air springs 35 or the like disposed between the bottom side of the cover 34 and the top side of the frame 29. As best shown in FlG. 2, the cover 34 is removably mountedover the opening, and preferably is swingably mounted upon a hinge 36 to one side wall 26 of the opening 23 and releasably connectible to the other side wall by means of a latch 37. As shown in FIG. 1, there may be two such air springs35, one on each side of a handle 38 on the top of the frame for lifting and lowering the wheel assembly in a manner to be described hereinafter. If desired, the air springs may comprise inflated cushions also useful as life preservers.

As previously described, and as best shown in FIG. 1, the front and rear Walls 24 and 25 forming the hull opening 23 slant upwardly and rearwardly with respect to the towing end of the hull to which hitch 18 is connected. In this manner, the force on the wheel of the assembly 27 will tend to move the frame 29 thereof more freely up into the hull opening 23. As shown in FIGS. 1 and2, the side and rear Walls of the hull opening may be reinforced by braces 39 and 40 connecting with the sides and bottom of the hull) i When the cover 34 is unlatched and swung aboutthe hinge 36 to an out-of-the-way position, the air springs 35 as well as the wheel assembly 27 may be raised from or lowered into the position shown in FIGS. 1 and 2. Since the fit of the frame 29 of the assembly within the opening 23 does not have to form a seal this operation is relatively simple and is, of course, facilitated by use of the handle 38. When the assembly has been lowered into position, and the air springs 35 placed upon the top side of the frame 29, the cover may be swung down upon the top side of the air springs and locked thereto by the latch 37 so as to depress them somewhat and thereby exert a yieldable force for holding the wheel 28 down in ground-engaging position and providing a shock absorber in the event the wheel engages an object along the ground.

When it is desired to convert the, boat from self-trailing to normal operating condition, the wheel assembly 27 is replaced by another assembly 41 which, as shown in FIGS. 3 and 4-, includes a surface 42 forming a smooth continuation of the boat hull when the assembly is positioned within the boat hull opening 23. More particularly, the surface d2 is formed on the lower side of a frame 43, which, similarly to the frame 29 of the Wheel assembly 27, has a cross-sectional shape between its upper and lower ends corresponding to; the hull opening for fitting relatively closely therein. This frame 43 also has a downwardly facing shoulder 44 for seating upon the upwardly facing shoulder in the boat hull opening; More particularly, the surface 42 which forms a smooth continuation of the boat hull depends from the shoulder 44 a distance equal to the vertical spacing of shoulder 3t? above the bottom side of the boat hull. Also, of course, and in keeping with the purpose of avoiding any turbulence when the boat has been converted to normal operating position, thedepending portion of the frame 43 fits closely within the lowermost portion of the opening 23. Again, of course, this relatively close fit is not designed to form a seal, but only to reduce to a minimum the likelihood of any turbulence across the joint between the frame and lower end of the hull opening.

When the assembly 41 is positioned within the boat hull opening, as shown in FIGS. 3 and 4, it too is held down upon the shoulder 30 by means of cover 34 and air springs disposed between the bottom side of the cover and the top side of the frame 43. As shown, the

top side of the frame 43 has the same elevation in its i supported position as does the top side of the frame 29,

the frame 43 does not have to withstand the forces upon the frame 29 which carries wheel 28. Thus, it may be relatively squat and held down by air springs 35 standing on end. Similarly to the wheel assembly 27 the assembly 41 may be lifted from and lowered into position by means of a handle 38 on the top side of the frame 43,

More particularly, and again as above described, the conversion of the boat between self-trailing and normal operating conditions is accomplished while the boat is still in the water. Thus, assuming that the boathas been used in the water, and it is desired to convert it from the operating condition of FIGS. 3 and 4 to the self-trailing condition of FIGS. 1 and 2, it would be moved into relatively shallow water, preferably of a depth just greater than the summation of its draft plus the height of the depending portion of the wheel when positioned for trailing. At this time, the cover would be moved to an out-of-the-way position and the air springs 35 and the assembly 41 lifted through the top end of the opening 23 to a suitable place for storing in the boat.

Since the top end of the opening is above the water level 13, there would be no flooding of the boat and, n fact, assuming that the water is relatively calm, there would be little or no splashing of water into the boat. This is particularly true since it is contemplated that the wheel assembly 27 could be almost immediately lowered into the empty opening 23 andsecured therein in the manner previously described. Thus, even though it is preferable to remove the wheel assemblies from within the boat when notin use, they would normally be carried in thetowing vehicle adjacent to the shallow water in which the conversion is being made. At any rate, the wheel, assembly is easily, lowered into position, at whi h time the wheel 28 thereof would normally be spaced a short distance above the underwater level. The boat could then be pulled forwardly by means of the hitch 18 to a position in which the wheels 28 would engage the underwater level and permit easy trailing of the boat out onto the land surface.

Obviously, conversion of the boat from the trailing condition of FIGS. 1 and 2 to the normal operating condition of FIGS. 3 and 4 merely involves a reversal of this process. Thus, the boat is first released from the towing vehicle and wheeled into the water, preferably to a level which will raise the wheels 28 a short distance above the underwater surface. In this way, the cover is easily unlatched and moved to an out-of-the-way position, so as to permit the air springs and wheel assembly 27 to be moved upwardly out of the hull opening and replaced by the assembly 41 which, when secured within the hull.

opening in the manner above described, disposes the surface 42 on its lower end as a smooth continuation of the bottom of the boat hull. At this time, the wheel assembly may be removed from the boat and the motor lowered into operative position for use in the water.

Preferably, the frame 43 of the assembly 41 is formed of a lightweight metal or plastic material, such as fiberglass or the like, which, in turn, may be hollow for storing purposes or filled with a flotation material such as styrofoam, so that the use of the assembly does not appreciably increase the normal weight of the boat. If further weight reduction is desired, the frame may be provided with openings, as in the case of the frame 29 of the wheel assembly '27. Ordinarily, since the frame is not required to resist forces which would act upon the wheel 28 or otherelements depending from the frame, it would not usually require any substantial reinforcement.

The hull 45 of the Hydrofoil type boat shown in FIGS. 5 and 6 is similar to the hull 10 of the other semi multihull boat above described in connection with FIGS. 1 and 4 in'that it is made up of a plurality of relatively distinct hull bodies 46. As is also the case of the hull 10, the hull of this Hydrofoil type boat has openings 47 in each of the outer hull bodies 46 which are adapted to receive interchangeable wheel assemblies (which may be identical to the wheel assemblies shown in FIGS. 1 and 2) and other assemblies 48 which convert the boat from its self-trailing condition into normal Hydrofoil condition. For this purpose, each of the assemblies 48 includes a frame 49 similar to the frame 43 of assembly 41 shown in FIGS. 1 to 4 in that it fits closely within the hull opening 47 and has a lower surface 50 which, with the assembly 48 secured in the hull opening, forms a smooth continuation of the bottom side of the boat hull.

As was also true in the case of the assembly 41, the assembly 48 is held down with a downwardly facing shoulder thereof resting upon an upwardly facing shoulder of the boat hull opening by means of a cover 34 adapted to be latched over the upper end of the opening by means of latch 37. As was still further true of the assemblies described in connection with the boat of FIGS. 1 to 4, the assembly 48 as well as the wheel assembly interchangeably usable therewith are yieldably held down by means of air cushions 35 disposed between the lower side of the cover and the top side of the frame of each such assembly.

In this type of boat, the frame 49 of each assembly 48 carries a depending hanger or support 51 which carries a foil 52 at a predetermined level beneath the bottom side of the boat hull. More particularly, the foils 52 carried from the assembly 48 on each side of the boat hull are at the same elevation so as to support the boat on an even keel as the foils glide through the water. As shown in FIGS. and 6, the support 51 extends upwardly into the frame 49 so as to reinforce same. Thus, as distinguished from the assembly 41, the frame of the assembly 48 receives the force of the water through the foils and thereby needs some reinforcement, which also provides force-transmission in a vertical direction between the air springs and the foils.

In a Hydrofoil type of boat, there are generally several foils like that shown at 52, and additional foils may be disposed forwardly to adequately support the boat at substantially the same horizontal level as the rear foils 52 suspended. by the assemblies 48; However, since the "boat only requires one set of wheels for trailing purposes,

the forward foils 52 may be supported from a different kind of assembly 53, and more particularly one which is merely removable from a hull opening 53a when the boat is converted to trailing condition. Of course, these openings would also permit removal of the assembly 53 upwardly through the top end thereof. Since it is not necessary to replace this assembly with a wheel assembly, the opening 53a need not be as large as the opening 4-7. In both cases, however, the openings as well as the frames of the assemblies disposable therein are slanted rearwardly and upwardly with respect to the towing end of the boat hull.

Similarly to those of the boats previously described, the hull 54 of the boat shown in FIG. 7 has a relatively fiat bottom such that it is adaptable for conversion from normal operating condition into a self-trailing condition. Thus, as shown in FIG. 7, this boat may be provided with a pair of hull openings 55 in its bottom side to receive wheel assemblies 56 therein similar to the wheel assemblies shown and described in connection with FIGS. 1 and 2. Thus, each assembly includes a wheel 57 mounted upon an axle 58 depending from a frame 59 of the assembly which is secured within the hull opening to maintain the wheel in engagement with the ground level 22 during trailing of the boat.

However, as distinguished. from those boats previously described, in the boat shown in FIG. 7, a hitch 66 is connected to the rear end thereof, and more particularly to the transom 61 across the rear end, as also shown in FIG. 8. Preferably, the hull openings are so arranged longitudinally of the boat to dispose their centers just beyond the center of gravity of the boat in a direction away from the hitch. The motor 14 shown in FIG. 7 is swingable upwardly out of a position across the transom so that a portion thereof will lie within a slotted opening 62 in the top edge of the transom (see FIG. 8). The inner end of the hitch which is connected to the transom includes a bracket 63 disposed beneath the slot 62 and thus intermediate the opposite sides of the boat. As shown in FIG. 8, this bracket has an opening 64 therethrough for receiving the end of a relatively stiff metal strap 65 in a position to be releasably connected to the bracket by means of fasteners 66 carried thereby and adjustable inwardly so as to engage within matching openings (not shown) in the end of the strap.

The strap 65 is bent at a location spaced below its innermost end and curved outwardly and then slightly upwardly toward its outer end. There is a socket 67 on its outer end similar to the socket 19 of hitch 18 for connection with a ball-type joint on a vehicle hitch 20 similar to that shown in Fi 1. As is also the case in conventional hitches of the type shown in FIG. 1, a roller 68 is carried by the outer end of the hitch 60 for supporting the end of the boat when the hitch is being connected. As will be apparent from FIG. 6, the lowermost curved portion 69 of the strap 65 is also useful for this purpose.

There is a loop 70 attached to the underside of the strap 65 intermediate its ends which is adapted to receive a rope 71 or other means for pulling the boat from the water and into a position for connection to the vehicle hitch 20. Preferably, the loop 70 is sufficiently large to receive an oar or other convenient tool aboard the boat to permit it to be pushed by means of the hitch into the water after it is detached from the vehicle.

In the embodiment of the invention shown in FIGS. 9 and 10, the opening 72 in the bottom side of the boat hull 73 is somewhat deeper than that of corresponding openings in the bulls of the previously described boats. Thus, in this embodiment, both the wheel 74 as well as the surface 75 adapted to form a smooth continuation of the boat hull are carried by the same assembly 76, so that, as illustrated in FIGS. 9 and 10, the assembly is reversible end for end to permit it to be interchangeably securable in a position for trailing the boat (FIG. 9) or a normal water operating position (FIG. 10).

For this purpose, the assembly includes a frame 77 which, similarly to the frame shown in FIGS. 1 and 2, is hollow so as to receive the upper portion of the wheel 74 and. to mount the axle 79 of the wheel toward its lowor end so as to dispose the wheel in position for engaging the ground level 22 when the assembly is secured in the position shown in FIG. 9. As in the case of the boats previously described, the frame is made lighter by holes 78 therein and the hull opening 72 has a shoulder 30 which faces upwardly to support a shoulder 81 on the frame when the assembly is in trailing position and a shoulder 82 on the frame when the assembly is positioned so as to dispose the surface 75 as a smooth continuation of the bottom of the boat hull, as shown in FIG. 10.

As will be apparent from the foregoing, the somewhat deeper hull opening 72 permits the wheel to be disposed in the upwide-down position shown in FIG. 10. In order to accommodate for this greater depth when the Wheel is disposed upright and in the trailing position of FIG. 9, there may be several air springs 35 disposed between the lower side of the cover 34 and the surface 75 on the side of the frame 77 opposite the wheels 74. Although not shown, it is contemplated that this cover would also be removably latchable over the upper end of the hull opening 72 so as to yieldably urge the assembly downwardly into the trailing position of FIG. 9.

On the other hand, when the assembly is reversed. endfor-end to dispose it in a position for rendering the boat useful in normal operations, as shown in FIG. 10, the lower side of the cover .14 will bear upon the end of the tire 74 so as to yieldably urge the assembly downwardly into secured position within the hull opening and the surface 75 into proper position as a smooth continuation of the boat hull. Thus, in this case, the rubber tire 74 acts in a manner analogous to that of the air springs 35.

In other respects, of course, this assembly is similar to each of the assemblies previously described in that the frame 77 fits relatively closely within the hull opening, but. without necessarily forming a seal therewith. It will also be understood that when this assembly is tobe converted between its self-trailing condition and normal operating condition, the cover 34 need merely be moved to anout-of-the-way position and the assembly lifted from the hull opening and reversed end for end prior to its being lowered back into the hull opening. Thus, this particular embodiment of the invention does not require that the operator of the boat carry another assembly for replacement purposes. On the other hand, it has the disadvantage of'adding weight to the boat inasmuch as the wheel portion of the assembly, including the frame 77 therefor, is always disposed within the opening of the boat hull and is always exposed to unfavorable elements.

In the Catamaran type of boat shown in FIGS. 11 to 14, the hull 83 includes a pair of separate hull bodies 84 which are connected together by a support structure 85 having its lower side normally raised above the water level 86. Since this type ofboat therefore has little draft, it needs stability in the form of sideboards 87 depending from each hull body S4 intermediate the opposite ends thereof. In this particular embodiment of the Catamaran type boat, it is propelled by means of one ormore sails 88 and has rearwardly mounted rudders 89 for directing same, although this type of boat hull may be powered in other ways.

In any case, however, this boat is also convertible between a self-trailing condition, as shown in FIG. 11, and a normal operating condition, as shown in FIGS. 13 and 14, wherein the sideboards 8'7 depend from the bottom side of each hull body 34. For. this purpose, and in accordance with the present invention, wheel assemblies 90 and sideboard assemblies 91 are interchangeably securable within openings 92 on the bottom side of each hull body. The wheel assembly 91) may be identical to the wheel assembly shown in FIGS. 1 and 2, and therefore need not be shown and described in detail. The asembly 91, on the other hand, is a good deal similar to the assembly 48 shown in FIGS. and 6 in that it includesa frame 93 of lightweight material which is relatively closely fittable within the hull opening 92 and which carries an element, comprising the sideboard 87, depending from its lower end.

There 'is a shoulder 94 on the frame 93 adapted to seat upon an upwardly facing shoulder 94a of the opening 92. More particularly, there is a surface 95 on a depending portion of the frame 93 which forms a smooth continuation of the boat hull when the assembly 91 is positioned within the hull opening 92 and from which the sideboard 87 is suspended, similarly to the suspension of the foil 52 in FIGS. 5 and 6. In this respect, if thought desirable, the upper end of the sideboards 87 may be extended into the interior of the frame 93 so as to reinforce the suspension of the sideboards as well as to provide a vertical load-supporting member between the air springs 35 beneath the cover 34 and the shoulder 94:: in the lower end ofhull opening 92. Since the manner in which the sideboard assemblies 91 may be interchanged with the wheel assemblies 90 will be obvious from the description of the prior embodiments of the invention, it need not be repeated herein. 1

This boat may be connected to a towing vehicle by means of hitches (not shown) on the rear ends of the hull bodies 84. More particularly, each such hitch may be similar to the hitch 6ft previously described, in which case the strap 65 thereof and rudder 89 may be interchangeably securable within a bracket 65 on the transom of each hullbody. That is, when the boat is to be converted to a self-trailing condition, the rudders 16 are removed from their mounting within such brackets andreplaced by the hitch straps.

With the hitch disposed at the rear end of the boat hull, the front and rear sides of each opening 92 slant upwardly and away from such rear end. In this manner, the forces on the wheel assemblies will move them more firmly into the openings during trailing of the boat.

The hull of the modified form of Catamaran type of boat shown in FIGS. 15 to 17 is similar to the hull 83 of the'boat shown in FIGS. 11 to 14 in that it includes a pair of separate hull bodies 96 which are spaced apart and connected together by a support str'ucture97 (FIG. 16) having its lower side normally raised above the water level (not shown). As was also the case of the boat shown in FIGS. 11 to 14, sideboards 98 extend downwardly from the lower end of each hull body 96 in its normal operating condition. Still further, as will be described to follow, each sideboard is replaceable by a wheel 1% for engaging the ground 99 in order to convert the boat to as self-trailing condition in which it may be propeled in any suitable manner. There is a hitch (not shown) at its forward or right hand end to permit the boat to be towed from left to right, as shown in FIGS. 15 and 17.

A substantially rectangular opening 101 extends from the lower end to the upper end of each hull body between upwardly and rearwardly extending front and rear walls 192 and 103. The sideboard assembly 104 shown inFIGS. 15 and 16 is similar to that shown in FIG. 14 in that it includes a frame 1115 upon which the sideboard 93 is carried. More particularly, the frame is generally rectangular in cross section so as to fit close- 1y within the hull opening 161 and has a shoulder 106 for seating upon a shoulder 107 facing upwardly within the hull opening so as to support the frame with the sideboard in proper position.

Inthis embodiment of the invention, the hull opening is somewhat deeper than those of the other embodiments, and thus an adaptor 108 having generally the same crdss section as the sideboard frame -is moved downwardly through the upper end of the hull opening to a position at least closely adjacent the upper side of the'frame. If desired, air springs may be disposed between the lower curved side of this adaptor and the upper side of the sideboard assembly frame so as to provide a cushion for the wheel. In any case, the adaptor 1218 is held down by means of a cover 109 adapted to fit over its upper end and be held down in such position by means of one or more rods 11% extending across it between the opposite side walls of the hull opening (see FIG. 16). The forward end of this cover may fit within a groove on the front wall 192 of the hull openingso as to make it more secure.

Similarly to the wheel assembly inFIGS. 1 and 2, the wheel assembiy 111 shown in FIG. 17 includes a frame 112 from which the wheel 10-1 depends in the self-trailing condition of the boat. Similarly to the frame 1115 of the sideboard assembly, this frame is generally rectangular so as to fit closely within the lower portion of the hull opening 101. It also has a downwardly facing shoulder 113 for seating upon the shoulder N7 in the hull opening so as to locate the wheel in the desired position. It may be of substantially the same height and held down in this position in the same manner as the assembly 194, so that the same adaptor 198 may be used in both instances. Thus conversion of the boat between normal operating. and self-trailing conditions merely involves raising and lowering of the adaptor to permit replacement of one assembly with the other. The adaptor has a rod 1418a at its upper end which not only servesas a brace, but also facilitates handling of the adaptor.

As distinguished from the sideboard assembly of the boat shown in FIGS. 11 to 14, the sideboard 98 shown in FIGS. and 16 is swingably mountable on the frame 105 by means of a pin 114 journaled at its opposite ends in the spaced apart sides of the frame 112. More particularly, and as shown in FIG. 16, these sides of the frame extend inwardly at their lower ends to define a slot 115 of approximately the same width as the sideboard 98. Thus, the sideboard is swingable about the pivot 114 between the normal operating position (solid lines in FIG. 15) and a retracted position within the hollow frame (dotted lines in FIG 15) so that it may be used or not used, as desired by the operator.

The sideboard is swung downwardly to and held in its normal operating position by means of a rope 116 connected to it adjacent the pin 114 and extending upwardly through or past the frame 195 as well as the adaptor 108. Thus, it is accessible to the operator above the cover 109, so that its free end may be tied to a suitable anchor when the rope has been drawn taut. As indicated in FIG. 15, the rope is guided within a groove along one edge of the sideboard and an idlcr pulley 113a on the frame 1455.

Alternatively, this rope may be released to permit the sideboard to be swung upwardly to the broken line position shown in FIG. 15, in which it may be secured by a pin (not shown) insertable through the hole 117 in another portion of the sideboard for fitting into a matching hole 117a in one or both of the sides of the sideboard frame 112. This pin and the holes are accessible to the operator through the upper end of frame 105.

In this latter position, the lower edge of the sideboard is disposed at substantially the same level as the lower edge of the frame 105, and the latter is in turn on substantially the same level as the lower edge of the hull opening in which it is disposed. Thus, except for portions of the slot 115 on the front and rear ends of the sideboard, the lower end of the sideboard assembly provides a continuation of the boat hull. In the retracted position of the sideboard the boat hull is interrupted even less than in the normal operating condition thereof. In any case, however, the interruption comprises only a portion of the cross sectional area defined by the slot 115, and it is in this sense that the sideboard assembly is said to provide a substantial continuation of the boat hull.

From the foregoing, it will be seen that this invention is one well adapted to attain all of the ends and objects hereinabove set forth, together with other advantages which are obvious and which are inherent to the apparatus.

It will be understood that certain features and subcombinations are of utility and may be employed without reference to other features and subcombinations. This is contemplated by and is within the scope of the claims.

As many possible embodiments may be made of the invention without departing from the scope thereof, it is to be understood that all matter herein set forth or shown in the accompanying drawings is to be interpreted as illustrative and not in a limiting sense.

The invention having been described, what is claimed is:

1. A self-trailing boat, comprising a hull having laterally spaced apart openings in its bottom side, means including a wheel assembly and a surface adapted to provide at least a substantial continuation of the boat hull, each of said wheel assembly and surface being separate from the hull and lowerable through the upper end of each opening into positions within said opening for converting said boat between self-trailing and normal operating conditions, and means for interchangeably securing each of said wheel assembly and surface in said positions within each said opening.

2. A self-trailing boat of the character described in claim 1, wherein said boat hull continuation surface is connected to said wheel assembly for end-to-end reversal within each said opening during said conversion.

3. A self-trailing boat of the character described in claim 1, wherein said wheel and boat hull continuation surface are carried by separate assemblies which replace one another Within each said opening during said conversion.

4. A self-trailing boat, comprising a hull having laterally spaced-apart openings in its bottom side, a wheel assembly positionable in each hull opening for transporting the boat over the ground, another assembly disconnected from the wheel assembly and positionable within each said hull opening to form at least a substantial continuation of the hull, and means for interchangeably securing the said assemblies within each of said openings when so positioned.

5. A self-trailing boat of the character defined in claim 4, wherein the hull includes at least two separate hull bodies with an opening in the bottom side of each, and said other assembly includes a sideboard depending from the boat hull continuation formed thereby.

6. A self-trailing boat of the character defined in claim 4, wherein the hull includes at least two separate hull bodies with an opening in the bottom side of each, and said other assembly includes a foil depending from the boat hull continuation formed thereby.

'7. A self-trailing boat, comprising a hull having laterally spaced-apart openings extending through the bottom side thereof, an assembly lowerable through the upper end of each opening and into landed position therein to dispose a wheel thereon in trailing position, another assembly disconnected from the wheel assembly and lowerable through the upper end of said opening and into landed position therein to dispose a surface thereon in position to form at least a substantial continuation of the hull, and means for interchangeably securing said assemblies in landed position within each of said openings.

8. A self-trailing boat of the character defined in claim 7, wherein each assembly includes a frame closely fittable within said opening, and said wheel is rotatably mounted on the lower end of the frame of the wheel assembly and said surface is disposed on the lower end of the other assembly.

9. A self-trailing boat of the character defined in claim 8, wherein said securing means includes means removably connectible over the upper end of each opening, and yieldable means compressible between the bottom of the last-mentioned means and the upper end of the frame of each assembly.

MD. A self-trailing boat, comprising a hull having laterally spaced-apart openings extending through the bottom side thereof, assembly lowerable through the upper end of each opening and into oppositely disposed landed positions therein, each assembly having a wheel at one end of engagement with the ground when the assembly is in one landed position and a surface on the oth r end adapted to form at least a substantial continuation of the hull when said assembly is in the other landed position, and means for interchangeably securing said assembly in each of said landed positions.

11. A self-trailing boat of the character described in claim 16, wherein said assembly includes a frame closely fittable within said opening and having said wheel rotatably mounted on its one end and said surface disposed on its other end.

12. A self-trailing boat of the character described in claim 11, wherein said securing means includes means removably connectible over the upper end of each opening, and said wheel has an inflatable tire which is compressible by the last-mentioned means when the assembly is secured in said other landed position.

13. A self-trailing boat, comprising a hull having laterally spaced-apart openings extending from its bottom side upwardly into the interior thereof, the upper end of said openings being above the water level of the boat when loaded, a wheel assembly including a frame closely fittable within each said opening and lo'vvcrable through the top end thereof to dispose a wheel carried thereby in a position to engage the ground for transporting purposes, another assembly including a frame closely fittable within the opening and lowerable through the top end thereof to dispose a surface thereon in a position to form at least a substantial continuation of the boat hull, and means for interchangeably securing each said assembly in operating position within each said opening.

14. A self-trailing boat of the character defined in claim 13, wherein said securing means includes an upwardly facing shoulder in each hull opening and a downwardly facing shoulder on the frame ofeach assembly for seating on the first shoulder, and releasable means for urging the second shoulder of each assembly down upon the first shoulder.

15. A self-trailing boat, comprising a hull having laterally spaced-apart openings extending from its bottom side upwardly into the interior thereof, the upper end of said openings being above the water level of the boat when loaded, an assembly including a frame closely fittable within each said opening and lowerable through the top end thereof to dispose a wheel carried on one end in a position to engage the ground for transporting purposes and reversible end for end to dispose a surface on the other end thereof 'in a position to form at least a substantial continuation of the boat hull, and means for interchangeably securing said assembly within said opening so as to dispose either the wheel thereof or the boat hull continuation surface thereof in operating position.

16. A self-trailing boat of the character described in claim 15, wherein said securing means includes an upwar-dly facing shoulder in each hull opening and oppositely facing shoulders on the frame of the assembly for seating on the first shoulder, and releasable means for urging each of the last-mentioned shoulders down upon the first shoulder.

17. A self-trailing boat, comprising a hull having laterally spaced-apart openings in its bottom side which extend to above the water level when the boat is loaded, a hitch on one end of the hull for towing it in one direction, an assembly including a frame closely fittable within each said opening and carrying a wheel therefrom to engage the ground, and means for securing the frame in the opening with the wheel in ground-engaging position, the front and rear sides of each opening as well as the close fitting front and rear sides of each frame slanting upwardly and away from the direction of travel of the boat.

18. A self-trailing boat of the character described in claim 17, wherein the hitch is on the forward end of the boat hull, and said sides of the hull openings and close-fitting sides of the frame slant upwardly and rearwardly from the forward end of the boat.

19. A self-trailing boat of the character described in claim 18, wherein the hitch is on the rear end of the boat hull, and said sides of each hull opening and the close-fitting sides of the frame slant upwardly and away from the rear end of the boat.

20. A self-trailing boat, comprising a hull having laterally spaced apart openings in its bottom side, an assembly having a frame closely fittable with each such opening, a wheel on one end of the frame, and a surface on the other end of the frame adapted to form at least a substantial continuation of the boat hull, said assembly being reversible end for end to permit the boat to be converted between self-trailing and normal water operating conditions, and means for securing said frame in each of said positions within said opening.

References Cited by the Examiner UNITED STATES PATENTS 2,890,466 6/1959 Bly 9--1 FERGUS S. MIDDLETON, Primary Examiner. 

1. A SELF-TRAILING BOAT, COMPRISING A HULL HAVING LATERALLY SPACED APART OPENINGS IN ITS BOTTOM SIDE, MEANS INCLUDING A WHEEL ASSEMBLY AND A SURFACE ADAPTED TO PROVIDE AT LEAST A SUBSTANTIAL CONTINUATION OF THE BOAT HULL, EACH OF SAID WHEEL ASSEMBLY AND SURFACE BEING SEPARATE FROM THE HULL AND LOWERABLE THROUGH THE UPPER END OF EACH OPENING INTO POSITIONS WITHIN SAID OPENING FOR CONVERTING SAID BOAT BETWEEN SELF-TRAILING AND NORMAL OPERATING CONDITIONS, AND MEANS FOR INTERCHANGEABLY SECURING EACH OF SAID WHEEL ASSEMBLY AND SURFACE IN SAID POSITIONS WITHIN EACH SAID OPENING. 